I have no idea what I'm wading into here, but a few things occured to me reading this:

Taking offense to something relies on status and perhaps more significantly on interpellation. Interpellation and its inherent insistence on dignity create barriers to what I'll call effective communication and introduce a rhetoric of respect. If we wish to be rationalists, really and truly, it seems like we must have a discourse that avoids insisting on respect for anyone or anything. We must all get thick skins, be willing to hear ourselves treated as objects of outside analysis and be willing to be ignored when we have bad ideas. Unwise, "offensive" comments like the one that seemed to kick off this discussion can be assayed because they are examples of poor thinking rather than because they are causes of emotional distress. Here, when it gets down to serious business, we should each have no more merit or status than our own arguments give us.

However, I have no idea how to sum this up in a maxim or otherwise implement this. What I offer is not a solution but an objective. I hope others can flesh it out.